Quiz Discussion

A 6 cm long cigarette burns up in 15 minutes if no puff is taken.For every puff, it burns three times as fast during the duration of the puff.If the cigarette burns itself in 13 minutes, then how many puffs has the smoker taken if the average puff lasted 3 seconds?

• 1] 17
• 2] 18
• 3] 20
• 4] 22
• 5] None of these

An athlete claimed that his timing for a 100 m dash should be corrected because the starting signal was gives by a gun fired from a point 10 m away from him and the timekeeper was standing close to the gun. The error due to this could be (in seconds) :

• 1] 0.03 sec
• 2] 0.1 sec
• 3] 0.5 sec
• 4] 0.7 sec

Two trains start from a certain place on two parallel tracks in the same direction. The speed of the trains are 45 km/hr and 40 km/hr respectively. The distance between the two trains after 45 minutes will be :

• 1] 2.500 km
• 2] 2.750 km
• 3] 3.750 km
• 4] 3.25 km

Three runners A, B and C run a race, with runner A finishing 12 metres ahead of runner B and 18 metres ahead of runner C, in another race of same type runner B finished 8 metres ahead of runner C. Each runner travels the entire distance at a constant speed. The length of the race is :

• 1] 36 metres
• 2] 48 metres
• 3] 60 metres
• 4] 72 metres

A train travelling at 48 kmph crosses another train, having half of its length and travelling in opposite direction at 42 kmph, in 12 seconds. It also passes a railway platform in 45 seconds. The length of railway platform is:

• 1] 200m
• 2] 300m
• 3] 350m
• 4] 400m

Amit travelled black to home in a car, after visiting his friend in a distant village. When he stated at his friend's house the car had exactly 18 litres of petrol in it. He travelled along at a steady 40 kilometres per hour and managed a 10 kilometres per litre of petrol. As the car was old, the fuel tank lost fuel at the rate of half a litre per hour. Amit was lucky as his car stopped just in front of his home because it had rum out of fuel and he only just made it. How far was it from his friend's home to Amit's home ?

• 1] 150 km
• 2] 170 km
• 3] 180 km
• 4] None of these

How long must a driver take to drive the final 70 miles of a trip if he wants to average 50 miles an hour for the entire trip and during the first part of the trip he drove 50 miles in \(1\frac{1}{2}\) hours ?

• 1] 54 min
• 2] 1 hr
• 3] 66 min
• 4] 70 min

The ratio of speeds of A and B is 2 : 3 and therefore A takes 20 minutes more time than B. What is the ratio of time taken by A and B?

• 1] 2 : 3
• 2] 2 : 5
• 3] 3 : 2
• 4] 3 : 5

A person wishes to reach his destination 90 km away 3 hours but for the first half of the journey his speed was 20 km/hr. His average speed for the rest of the journey should be :

• 1] 4 km/hr
• 2] 0.75 km/min
• 3] 1 km/min
• 4] None of these

A car traveled first 36 km at 6 km/h faster than the usual speed, but it returned the same distance at 6 km/h slower than usual speed. I the total time taken by car is 8 hours, for how many hours does it traveled at the faster speed ?

• 1] 4 hours
• 2] 3 hours
• 3] 2 hours
• 4] 1 hours